Furnace



Octzz, 1929. E. E BILLQW l 1,732,876

FURNACE Filed Nov. 5, 1927 f5 Sheets-Sheet. 2

Hy M M WMM oct. 22, 1929. E. E. en mw 1,732,876

4 FURNACE l Filed Nov. 5. 1921 s sheets-sheet s @www illled withunburned fuel explode upon relighting vthe iiame. An im- Patented Oct.22, 1929 nLmEn n Mirow, or EvANsroN, ILLINOIS li'UBNACE Application lledNovember 5, 11927. Serial No. 231,385.

rlhe present invention relates to improvements in furnaces, particularlyfurnaces adapted to burn fuel such as powdered coal or oil.

ylhe-primary object of the present invention resides in the provision ofa novel furnace having a variable combustion chamber.

y ln furnaces, particularly oil burning furnaces, subjectato a variabledemand, the supply of fuel may be regulated to vary the size of theHaine from each burner nozzle. Thus, when one of these furnaces is beingoperated under a heavy load, the :flame is`relatively large, and whensaid furnace is beingoperated under a small or minimum load, ortemporarily under no load, the flame is relatively small. ln the last islikely tovbe extinguished in the ,combustion chamber by draughtsandbecause of the relatively low surrounding temperatures. As a result, thecombustion chamber may become vapors which may portant object of thepresent invention therefore resides in the provision of a furnace havinga relatively large main combustion chamber, a relatively small auxiliarycombustion space or zone opening to said main combus-v tion chamber, theHaine from l urn in the main combustion chamber when large, but will beconfined to the small co bustion space when small, thereby in the la tinstance protecting it maintaining it in a zone of relatively high local temperatures.

Another object -resides in the provision of and means for ,socontrolling a' furnace having a combustion chamber with a maincombustion zone and one or more relatively small, contiguous andprotectedauxiliary combustion'zones, with a burner in each ci thelatter., A l v l further object-ofthe invention is to provide a. furnacehaving a grate for admitting a stream olcombustion air, a burner havinga variable fuel supply and aA constant air sup` ply scient to maintainsubstantially complete combustion of a minimum fuel supply, and directedto Hatten out the stream of fuel, and to conline it to a small zonecontiguous instance, the small flamethe'burner nozzle that it will fromdraughts and to the grate, and means for directing a blast of airagainst the stream of fuel mixture leaving the burner nozzle so as todirect the latter into the stream of combustion air over the grate.

@ther objects of the invention are to provide a new and improved furnacein which there is an ellicient and complete combustion of fuel, in whicha homogeneous fuel mixture is obtained in the main combustion zone', in60 which theincoming combustion air is utilized to protect the walls ofthe furnace in the neighborhood of the combustion zone against excessiveheat, in which the secondary air is `admitted in such a manner thatcombustion taken along line 1--1 of Fig. 2.

Fig. 2 isa horizontal sectional view taken along line 2 2 of Fig. 1.

Fig. 3 is a horizontal sectional view taken 80 along line 3-3 of Fig. 1.f

Fig. 2l is a longitudinal sectional view of the Aburner nozzle takenalong line 4-4 of Fig. 2?.

While the invention is susceptible of vari- -ous modifications andalternative constructions, I have shown in the drawings and will hereindescribe in detail thepreferred embodiment, but it is to be understoodthat I do not thereby intend to limit the invention to the specific formdisclosed, but intend to cover all modifications and alternativeconstructions ialling withinthe spirit and scope of the invention asexpressed in the appended f y i 5 Referring to the drawings, I haveshown the exemplary embodiment `of my invention incorporated in afurnace structure having a vertical and preferably cylindricalcom'bustion chamber l0, and mounted ona suitable ,10'

support 11, but itv will be understood that the invention is applicableto. dilerent kinds of furnaces. In the' present instance, the chamber isdefined by an inner cylindrical wall 12. Heating tubes 13 Yare suitablydisposed inside and adjacent the peripheral wall 12.

y Preferably, a preheater for incoming combustion air is provided aboutthe outside of the wall 12. In the present instance, the preheatercomprises an annular space or chamber 14 defined aboutthe wall 12 byfanouter concentric lwall 15, and closed at the upper and lower ends byannular end walls 16 and 17 respectively. VA'plurality of suitable tubes18 extend. longitudinally through thespace 14 between the end walls 16and 171 Of the tubes 18, the upper ends communicate with the combustionchamber 10, and the lower ends open into a suitable exhaust duct 19. Agenerally cylindrical slightly tapered baille sheath 20 extendsdownwardly into the chamber 10, and serves to direct the productsscribed taken by itself forms no partof the present invention, and isdescribed for the purpose of fully illustrating the invention.

The present -invention deals primarily with the burner section of thefurnace, and

` with the control of thel fuel and air supply j to the combustionchamber 10. In the press l support 11 and about the wall 15,

nt instance, the burner section constitutesa'dome or head 23 closing theupper end of the combustion chamber 10. To support the dome 23,'preferably aplurality of vertical columns 24, four inthe presentinstance, are securedin' equally spaced relation on the and extendupwardly toN the somewhat abovethe wall-12`. The columns 24, may be constructedin any suitable man- 4 Miner, as for example byvsecuring twoangle bars` 25 together withtwo legs extending 1n directly oppositedirections ,next to thewall 15, and by securing a strengthening str1p 26between the bars 25.

. angle bars 27, at its outer peripheral edge to the inside of the wall15 near its upper end, is an annular horizontal wall 28 which projectslation thereto. The. inner 'peripheral'edge of the wall 28 is turneddownwardly to form a dependingcylindrical flange 29 which extends intothe. sheath 20 and over the inner upper coils of the heating. tubes 13-to protect the latter from excessiveA heat.`V

- sealing the space height of the wall 15 andA over the wall 16 and inspaccd're- Thev upper end'of the sheath 20 is securedA to the undersideof thew'all 28 by means of an angle rim 30 concentric with the iange 29,thereby between the upper end of the sheath and the wall 28 so as todirect all of the products of combustion downwardly over the lower endof the sheath.

Secured to the Wall 28 in any suitable mannerand in equally spacedrelation along its inner peripheral edge are a plurality, four in thepresent instance, of upwardly and in. wardly inclined arcuate walls 31.Secured to the side edges of .the walls 31 in any suitable manner area-plurality of U-shaped wall members having side walls 32 and a top wall33. The lower edges of the side walls 32 rcst on the wall 28. TheU-shaped wall members define compartments 34, four in the presentinstance, the inner ends of which open into the combustion chamber 10,and which constitute relatively small auxiliary combustion chambersformingl part of the combustion chamber 10 but not subject to thedraughts therein. Preferably, the compartments 34 are locatedintermediate the columns 24.

Secured-to the upper ends of the columns 24 and in abutting relationwith the upper edge of the wall 15 are a plurality of arcuate memberseach having a horizontal wall 36 parallel to the wall28, and an upwardlyand inwardly inclined wall-37 parallel to one of the walls 31. The walls36 and 37 are suitably spaced from the walls 28 and 31 by spacers 38,todefine air'passages 39, and the parts are held in assembled relation byany suitable means such as bolts 40. Suitable inwardly extending arms41secured to the columns 24 and the walls 36 by any suitable means such asangle plates 42 are'secured to the walls 37 as by welding to support thelatter.

Secured to the side edges of the walls 37 as by welding are a pluralityof U-shaped wall members each having side walls 43 and a top wall 44held in spaced relation respectively to thewalls 32 and 33 to define anair space 45 therewith about the compartments 34and opening into thepassages 39. The side walls 43 rest on the walls 36. Suitable spacermembers 47 are secured between the inner and outer walls of the airspaces 45, and the parts are clamped together by means of bolts 48.

Suitably secured to the outer ends of the U` shaped wall members are aplurality of end Secured in any suitable manner, as by walls 49` whichclose the outer ends of the compartments 34 and the air spaces 45.

Formed on the upper end of the wall 15 betweenthe columns 24 are aplurality of arcuate chambers 50 each havingan outer arcuate wall 51,end walls 52 and a bottom wall 53. The upper edge of thewall 51 issecured to the underside of the wall 36, and the inner jedges of thewalls .52 and 53 are secured `to -the outside of the wall 15. Thechambers 50 communicate through openings 54 and 55 re spectively to thechambers 14V of the preheater and the compartments 34 and air passages39.

a downwardly, and

- stream of air against the stream of fuel to is such that whenProjecting into the outer ends of the `conupartments 34 are a pluralityof suitable burners 56, one for each compartment. ln the presentinstance, each burner 56 comprises a 5L water cooled nozzlef57longitudinally adjustable in a sleeve 58 in the end wall 49, and

adapted to discharge a stream ofva suitable fuel and air, such as fueloil and air.

Referring to F ig. 4, the nozzle 57 preferm ably comprises a dischargeoriice68. A tube 69 opening at the orifice 68 is adapted to be.

connected through a hand control valve 70 to a fuel supply pipe 71adapted to be connected to a suitable"source (not shown).

i5 Surrounding the tube. 69 is a sleeve 72"*Which is open to an airsupply line 73 adapted to be connected to a suitable and preferablyconstant source of air undeil 4Vpressure (not shown). The sleeve 72opens about the tube 2o 69 to the oriice 68 and also to an air dischargeflatten the latter and to direct it downwardly at an angle onto thebottomwall of the chamber 34. 'lhe'air supply through the pipe 73 thesupply of fuel-is adjusted to a minimum fora small Haine, it will besuilicient to produce substantially com- Jplete combustion; To protectthe wall 2S from excessive heat, Pa plate 59 is adustabl mounted on andin spaced relation to the wal 28. This plate is held in position bysuitable guide members 60 and has an arm 61 extendingloutwardly throughthe walls 15 and H 5l by which it can beadjusted. The plate a0 59` is soadjusted that the fuel and air from the burner 56 will impinlgethereon'unless raised out of Contact therewith as will be hereinafterdescribed. rIlhe plate Y 59becomes highly heated, toI aid in keeping asmall stream i ited.

flattened `streamll of and hence serves Means is provided for directingt e air entering through the openings into the chamber 34 over the plate59 and against the underside of the fuel stream so as to raise 'the 50latter from the plate 59 andfdirect same into the combustion zone in thechamber l0. This means comprises a baille plate 62 suitably secured to Ythe opening 55, and slightly inclined down- '55 'wardly to a point overrthe plate 59.

Mounted' in the center of thedome v23-is a suitable grate 63 forsupplying the necessary combustion air to theJ chamber 10.' Preferably,the grate 63, is round and has a peripheral dange 64at its upper edgelresting on the upper and inner edges ofthe walls 31 and 33. Theopeningat the upper and linner edges of .the walls 37 and44 directly overthegrate 63 is closed by a suitable plate 65. The gratel. A f5 Y63andthe plate 65 delinean air chamber66 inv the chamber 34,4

the inside of the wall l5 just over t which communicates with the airpassages 39 and the air spaces 45. It will thus be noted that all of theinner surfaces of the dome 23 exposed to direct heat are air cooled.'lhe center of the grate 63 is formed with suitable air inlet means,such as a plurality of perforations 67, to admit a central blast of airto the combustion chamber l0.' Preferably, the center of the pan 63 ispressed inwardly or upwardly to orientate the perforations 67 toward thecenter ofthe chamber l0 so as to heepthe llames `from impinging directlyon the inner coils of the tubes 13. To prevent the ame from any one ofthe four burners 56 fromv entering, or coming close to one of the otherburners, the grate 63 is formed in the shape of a pan depending into theupper end.

of the chamber 10.

ln operation, When the furnace is under a load, air is supplied by thefan 21 to the chambers 34 and the grate 63. rlhe air passes 'throughJthe grate63 into the combustion chambelO. Each burner discharges a flattened stream of fuel with some air, and this stream is directed by theair entering thev chamber 34 into the main combustion chamber 10 and thestream of air from the grate 63 where it is consumed. The incoming airwhile itself at a high temperature still serves to cool the inner wallslof the dome 23.

When there is temporarily no load or avery`smallv load the supply offuel tofeach burner .56 is reduced thereby causing the flame to Withdrawinto the small chamber, 34. The supply of'air to the chamber 34` isstopped so as to permit the small flattened stream of fuel from theburner 56 to impinge on the hot plate 59'.l With the fuel supply reducedto a small stream, enough air enters through the nozzle/5.8 to effectcomplete com. bustion in the chamber 34. vThus the smally stream of fuelburns quietly Without smoking and 1s protected from the draughts andlowering temperatures in the main combustion chamber/ 10. The chamber 34being small is readily maintained at a relatively high temperature. l-fthe small llame werein the mam chamber l0, it probably would soon besnuied out, and the charnber. 10 would lill with unburned vvapors sothat ex lesions might result.

lt w1 1 be evident that the constructiorri simpleA and inexpensive, thatthere will he no oveg-heating of the parts, ane. that a homogeneous fuelmixture and hence complete combustion will be obtained. '.lhe parts IOLdescribed herein can be made of any suitable I combination, a i

direct it to said large space when full and to confine it to said smallspace when small.

2. A furnace having in combination, a combustion chamber having acentral combustion zone and an auxiliary-confined combustion zone, aburner, and means for selectively directing the flame from said burnerto said main zone or p for confining said flame to said auxiliary zone.

3.. A furnace having, in combination, a combustion chamber, a burnerhaving `a variable fuel supply and a constant air supply sufficient tomaintain substantially complete combustion of a minimum fuel supply, and

having means for directing the air in a Jet across the fuel jet toflatten and deflect the latter against one vvalll of said chamber, andmeans for directing a stream of iiuid against the underside of said fueljet tofkeep the latter away from said Wall and-to direct it to Withoutsaid chamber when desired.

4. A furnace having, in combination,l a combustion chamber, a wallforming part of said chamber, a plurality of spaced and double-walledcompartments formed in said Walll and opening into said chamber, aplurality of burners one lin each compartment adapted to direct a streamof fuel into sai-d chamber, a depending member in said wall between saidburners, and formed with air inlet means, and means for directin airthrough said compartments into said c amlber, and air over said Wallthrough said member into said chamber.

mounted. in each 'first mentioned means.

' combustion chamber, means formin 5. A furnace having, in combination,a combustion chamber, a Wall forming part of said chamber, a pluralityof spaced compartments formed in said Wall and opening into saidchamber, a plurality of burners one in each compartment adapted todirect a stream of fuel into said chamber, a depending member in saidWall ,between said burners, and formed with air inlet means, and meansfor directing air. over said .wall through said member into saidchamber.

6. A furnace having, in combination, `a combustion chamber, a wallforming part pf said chambensaid Wall being formed with a plurality ofdistinct, relatively small and spaced chambers opening to saidcombustion chamber, and a plurality of burners .one

and adapted to direct a stream of fuel mixture therefrom into saidcombustion chamber.

7. A furnace having, in combination, a combustion chamber, a wallforming part of said chamber, said wall being` formed with air inletmeans, means for directing air over the outside surface of said walltosaid inlet means, and a plurality of burners mounted in said fvalll inspaced relation about said 8. A furnace having, in combination, a an auxiliary combustion space distinct rom and of said spaced chambers openingto said chamber,',.and a burner adjustably mounted in said spacefsaidburner having means for adjusting the fuel supply so as to vary theflame from a size extending into said chamber yto a size substantiallyconfined to. said space.

9. A furnace having, in combination, a combustion chamber, a domeclosing said chamber, said dome being formed with a plurality of spacedcompartments opening into .said chamber, and having double Wallsdefining air filled spaces, and a plurality of burners one mounted ineach compartment and adapted to direct a stream of fuel therethroughinto said combustion chamber.

10. A furnace having, in combination, a combustion chamber, a relativelysmall compartment opening to said chamber, a burner adaptedl todischarge a streamof fuel into said compartment and against a Wall ofsaid compartment, means for adjusting the fuel supply to said burner,and means or directing a stream of air over said Wall to raisesaidstream of fuel therefromv and direct it into said chamber.

11. A furnace having, in combination, a combustion chamber, a Wallforming part of said chamber, a plurality of spaced compartments in saidWall .and about said chamber, a plurality of burners one in eachcompartment and means for directing air through said compartments intosaid chamber.

12. A furnace having, in vertical chamber, a wall closing'the upper endof said chamber, a plurality of burners mounted in spaced relation insaid Wall and combination, a.

trally in said Wall and depending between said burners, and means 'fordirecting air over the outer surface of said .wall and through saidmember into said chamber.

13. A furnace having, in combination, a vertical combustion chamber, aplurality of supporting columns disposed about said chamber, a wall'supported on said columns and closing the upper end of said chamber, aplurality of compartments formed at the periphery ofl said Wall andopening therethrough into said chamber, a plurality of burners one ineach compartment and adapted to direct a stream of fuel into saidchamber, means for directing air through said compartments into saidchamber, and means for directing air over said Wall into said chamber.

14. A furnace having, in. combination, a furnace chamber having a.central draft having a space out of the central draught, ad- 'ustablemeans disposed in said space, a burner having a nozzle adapted to directa stream of fuel against said means, and means for directing air oversaid means out of said space into said furnace chamber. s 15. A furnacehaving, in combination, a combustion chamber, a compartment opening intosaid chamber, means mounted on and in to carry said fuel fill spacedrelation to the bottom Wall of said compartment,` said means beingadjustable lengthwise of said compartment, a burner having a nozzleadjustably mounted in said compartment and adapted to direct a stream offuel therefrom aga-inst said means, and

means for directing a stream of air over said Erst mentioned means toremove said stream of fuel therefrom and direct same into said chamber.

16. A furnace havmg, 1n combination, a combustion chamber, acompartment, aburnner in said compartment adapted to direct xed mysignature. a l

ELMER E. BILLOW.

